City of Cedar Falls Department of Community Development Inspection Services Division 268-5161 Residential Deck Requirements 2015 International Residential Code
These general requirements were compiled for convenience as a general construction guide.
Building Permits are required for the construction or installation of wood decks whether supported by the dwelling/structure or fully independent from any dwelling/structure. I
Application Process 1. Complete supplied site plan form, including scaled plan of the property and proposed deck location as per instructions. Check with Zoning Administrator for required setbacks. 2. Complete building permit application with all applicable information including framing member sizes, footing dimensions and quantities, and decking material. Complete a construction diagram with dimensions and framing member sizes/spacing. 3. Submit site plan, permit application, construction diagram, and fee payment to Inspection Services (lower level of City Hall) 4. Permit fees are base~ on the determined value of the project. Fee Schedule is available upon request, contact Inspection Services) 5. After site plan and construction plan have been approved a building permit will be issued and work can begin.
Inspection Process 1. Once a permit has been issued, complete each required inspection as listed on the yellow permit card. Typical inspections required for a deck project are as follows:
a. Post Hole Footing -When po~;t holes have been dug; prior to concrete pour I b. Framing -W:hen posts, beams, ledger, and joists are complete; prior to installing decking c. Final - Completion of project including decking, stairs, guardrails, and handrails 2. Post the yellow inspection card on site so it is clearly visible and accessible for the inspectors 3. It is the responsibility of the permit holder to request all needed inspections.
Construction Footings Minimum depth= 42" for frost protection. Footings on sloping or terraced grade shall be measured to ensure coverage both vertically and horizontally. Minimum diameter= 8". Where joist length exceeds 12', post spacing exceeds 8', or the footing support both the deck and a roof cover footing diameter will need to be increased to 12" diameter. Footings shall be free of organic material,, loose soils, and ground water Footings shall be protected from freezing during cold weather conditions Framing Wood exposed to the exterior elements shall be approved treated lumber or wood with a natural resistance to decay (the! heartwood of bald cypress, black locust, black walnut, cedar and redwood I species). The treated lumber shall bear a grade stamp indicating lumber species, grade identification, quality standards number, and exposure condition. Deck Ledger minimum ~ize 2"x8" or equal to joist depth, whichever is larger. Ledger is required to be attached to the house with minimum Yz" diameter double-dipped galvanized bolts long enough to penetrate the house rim board (or other approved fasteners). In addition, a minimum of 2 Tension Hold Down Devices shall be insta1lled for lateral load connection. See figures page 2. TABLE RS07.2 DECK LEDGER CONNEcCTION TO BAND JO!ST'b (Deck llve load .. 40 p11I, deck dud k>ed "' 10 psf, snow load s 40 p11I) JOIST SPAN CONNECTION DETAILS &'Md .... 6'1"toe' 1'1" to 10' 10'1" to t2' 12't"toH' 14'1" to 16' 1&'1" to ta' On-contor apaelng of fnt9IHIN
'/2-inch diameter Ing scn:w with 'lrinch 30 18 15 II m!lllirnum sh('.a lhinz" 4 B 13 IO 1 1 /..- inc.h dirul'll)tcr boll with / 2-inch maximum • shca1hing• :\6 36 34 29 24 21 19
'/,-inch diameter bolt with I-inch maximum :\6 29 shcalhing" 36 24 21 IR lti
• 1i STAGGER FASTENEFtS "' ::E IN2 ROWS
0 0 "DISTANCE SHALL BE PERMITTED TO BE REDUCED TO 4 .5" IF LAG SCRE'IJS Ji•RE USED OR BOLT SP.ACING IS 10- c ~ REDUCED TO THAT OF LAG SCREWS ..:q o o\ h 10 ATTAOH 2 X 8 LEDGERS TO 2 X B BAND JOliHS. 2" MIN I:EDGER __/ l LAG SCREW OR BO!.. T 314" MIN.
For SI: I inch= 2' .4 mm. FIGURE Rl;o7.2.1(1) PLACEMENT OF LAG SCREWS AND BOLTS IN LEOGERS
\ '"'°'-000-0l'l!l-.ll#I. TUll!l"l>I CF~
I'\ CXlA _A,....() -l ~AT t·--Ollj~,_TO Jor9T-t<>~
11'1.CXlA X>lflT .JC>!IT
l'.orSI · I 1acfl- ~4- . AG ..... 607.2.31(1) Mat ATIACNllSfT ~ lATSRAl LOADS
*1500 lb. rated hold down - 2 required, located within 24" of each end of the declk
SHEATHING NOTE: SIDI~ THIS DETAIL IS APPLICABlE WHERE R..OOR JOISTS ARE R..ASHING FOR PARALLEL TO DECK JOISTS WATER TIGHTNESS
- APPROVED JOIST HANGERS
2"MIN. ~ 2x LEDGER WITH F.'~TENERS IN ACCORDANCE WITH TABLE R507 .2
HOLD·DOW!li DEVICE MIN 750 LB CAPACffY AT 4 LOCATIONS. EVENLY DISTRIBUTED ALONG DECK AND ONE WITHIN 2· OF EAC Ef>.O OF THE LEDGER HOLD-DO\o\IN DEVICES SKA.LL FULLY ENGAGE DECK JOIST PER HOLD-DOWN MANUfACnJRER.
A FULLY THREADED •1. · DIAMETER LAG SCREW PREDRILLEO W/ MIN. 3• PENETRATION TO CENTER OF TOP PLATE. sruDS. OR HEADER
Fur SI: I inch= 2~.4 mm . I foot= JO... 8 mm.
FIGURE R507.2.3(2) DECK ATTACHMENT FOR LAliERAL LOAllJS *750 lb. rated hold down - 4 required, evenly spaced with one within 2" of each end of the deck Deck Ledger shall be flashed to prevent water from contacting the house. Deck bearing beams shall be minimum 2-ply nailed together with 2 rows of 10dx3" nails spaced 16"o.c. Beams shall be allowed to cantilever a maximum of X the actual beam span. Beam shall be attached to posts by either Notched Post or Post Cap method.
BEAM
APPROVED BEAM ~ POST CAP
NOTCH POST 1511> Ml
NOTCHED PQST PQST CAP
For SI: I in.:h = 25A mm.
FIGURE RS07.7.1 OF.CK BEAM TO DECK POST
Deck bearing beam spans in accordance with Table 507.6
TABLE R607.6 DECK BEAM SPAN LENGTffSLb (ft. - In.) DECK JOIST SPAH LESS THAN OR EQUAL TO: SPECIES" SIZE" (leet) 6 8 10 12 14 16 18 2-2 x 6 6-11 5-11 5-4 4-10 4-6 4-3 4-0 2-2 x 8 8-9 7-7 6-9 6-2" 5-9 5-4 5-0 2-2 x 10 10-4 9-0 8-0 7-4 6-9 6-4 6-0 2-2xl2 12-2 10-7 9-5 8-7 8-0 7-6 7-0 Southern pine 3-2 x 6 8-2 7-5 6-8 6-1 5-8 5-3 5-0 3-2 x 8 I 10-IO 9-6 8-6 7-9 7-2 6-8 6-4 3-2xl0 13-0 11-3 I0-0 9-2 8-6 7-11 7-6 3 -2 x 12 I 15-3 13-3 11-10 10-9 10-0 9-4 8-IO
Deck posts shall be treated for direct contact with earth {UC4B or UC4C) and connected to concrete footings with approved post connector. Maximum height restrictions: 4"x4" = 8' 4"x6" =8' 6"x6" = 14' Deck joists shall be connected to the ledger using approved metal joist hangers. Joist tails shall have a minimum 1 Yz" bearing on wood or metal joist hangers. A rim board shall be installed on the joist tails to prevent rotation. Joist spacing shall be determined by span and decking material. See table below for allowable spacing for wood decking, plastic/composite decking shall meet the manufacturer's installation specifications TABLE R507.4 MAXIMUM JOIST SPACING MAXIMUM ON--CENTER JOIST SPACING MATERIAL TYPE AND NOlllNAL SIZE Perpendicular lo iol•t l>Ygonal lo Jol•I" I '/.-inch-thick wood 16 inches 12 inches
2-in~·h-thick wood 24 inches 16 inch<.'S Plaslic composite In accordance with Section R507.3 In accordance with Section R507.3
For SI: I inch= 15.4 mm, I fOOf. =~.l! mm. I dcgroc = o.01745 rdd. a. Maximum angl~ 01 45 degrees from pcfl>'-'Odkular fc,.- wood dccl boanh.
Maximum allowable spans for wood deck joists in accordance with Figure 507 .5. Deck joists are allowed to cantilever not greater than X the actual adjacent joist span. TABLE R507.6 DECK JOIST SP... .NS FOR COMMON LUMBER SPECIES' (tt. - In.) SPACING OF DECK JOISTS WITH NO CANTILEVER• SPActNG OF DE.CK JOISTS WrTH CANTILEVERS"- SPECIES• SIZE (Inc,,_) (Inc'-) 12 16 24 1 2 16 24 2><6 9-11 9-0 7-7 6---8 6---8 6-8 2><8 13-1 11-IO 9-8 10-1 10-1 9-8 SouU1crn pine 2x 10 16-1 14-0 11-5 14-6 14-0 11-5 1x 12 18-0 16---6 U-6 18-0 16-6 13-6 2 x 6 9-6 8-8 7-2 6---3 6-3 6--~ ~xu;.l!ls fir-larch" .. 2x8 12-6 11 - 1 9-1 9-5 9-5 9-1 hcm- ri.-l spruix-pine-fir.&1 2X 10 15-8 13-7 11 - 1 13-7 13-7 11 - 1 2X 12 18-0 i5-9 12-10 i8-0 i5-9 12-10 2x6 8-10 8-0 7-0 5-7 5-7 5-7 Redwood. we.stem cedars, 2x8 11-8 10-7 8-8 8-6 8-6 8-6 pondc.-osa pincci. 1x IO 14-11 13-0 10-7 11-3 12-3 10-7 red pine" 2X 12 17-5 15-l 12-4 16-5 15-1 12-4 All nails shall be double-dipped galvanized or stainless steel. Double-dipped galvanized blots are required to be minimum Yi'' diameter. Decks more than 30" above grade shall be protected by a guardra il not less than 36" in height. Balust1~rs or other infill com ponents shall be spaced such that they will not allow the passage aof a 4" sphere. Guardrails shall be constructed so t hey wit hstand a 200 lb. conce!ntrated load applj,ed to the top of the handrail. Infill components shall withstand a 50 lb./sq. ft. lateral load. Solid blocking in between floor joists may be necessary to meet these requiremE!nts. Stairs servicing deck shall have a maximum rise of 7 %" and minimum tread depth of 10". The minimum width of the stairs shall be 36". Open risers are only permitted if the height above gra de is 30" or less. Stair treads shall be supported by concealed cleats or cut stringers. Guardrails shall be installed on the open side of stairs if the overall height of the deck is greater than 30" above grade. Handrails shall be installed on at least one side of any stairway with 4 or more risers at a height of 34"-38" above the front edge of each tread. The handrail shall be continuous and un-interrupted from the top riser to the bottom riser. The handrail shall have returns or terminate to a post at the top and bottom. Handrails installed along a wall or solid guardrail shall be spaced not less than 1 Yi" off the wall or guardrail. The handrail shall be graspable. IYI'
1.,.-IDrn
NOTE:
These are examples of typical allowable handrails. Contact the Inspection Department for specific requirements for Type I or Type II handrails.
These requirements are for uncovered/unenclosed decks and may not be acceptable for covered decks, screen rooms, 3-4 season rooms, or commercial/multi-family decks. Contact the Inspection Department for specific requirements. ng
ullti hou fto« ooostruction
i t
'*"'*• • top 8Ad bolorn wlll (1 )lf8 wood MnW 01 (2)111 poel·f 0.135• nominal I
s·-o· maximum tween posts stair guard is required for --~-- ataira with e total riae of 30" Of' more; see GUARD REQUIREMENTS for mote Information
stair guard height· 34• min. measured from nosing ol _,.,
0 0 Openings for required guarda on lh Tnanguler openmg shalt aides ol stair traada eheU not allow not pefTilit the p a e 8 aphefe •-318" to pua lhrough. of a 6" d ameter sphere.